Educate yourself

The most important activity a family member caring for someone with Alzheimer's or related memory disorder can do is to educate themselves. This will save a lot of frustration later on. Learn what is happening to the brain, what common responses are from the person with the disease, and how you must and I say must if you want to be a good caregiver), and what and where your local resources are. The best place to start is the Alzheimer's Association website. It is www.Alz.org. Contact your state's association and learn. Many, if not all, have 24/7 hot lines for caregivers to have 1:1 help understanding common challenges.
If there has been no formal diagnosis, get one from a neurologist, neuropsychologist,geriatrician or physician educated in Alzheimer's. Don't settle for "It is just old age." There are more than 100 causes for dementia (a change in brain function atypical of persons of that age). Many are reversible. All are treatable.
Get books on the subject (like mine, Matters of the Mind)or Learning to Speak Alzheimer's by Joanne Koenig Coste. There are many good ones.
Google Alzheimer's on the web and you'll find thousands of referenced papers and resources (this can be a daunting task). For personalized education there is telephone coaching through StilMee.com. We have coaches with many years of experience in dementia care, both personal and professional, who are there to be your trusted advisor and supporter. Go to StilMee.com and email a coach for a preliminary talk with her.